The father of Android Andy Rubin will be leaving Google's mobile operating system division to take on a new role at the company and is replaced by Sundar Pichai, the head of Chrome.

Andy Rubin is the creator of Android, the mobile operating system acquired by Google in 2005. (Credit: Reuters)

Android Inc was founded by Rubin in Palo Alto, California, in 2003 and acquired by Google two years later. It became available on the first commercially available handset, the HTC Dream, in October 2008.

Writing on the official Google blog, CEO Larry Page said that in 2004 "most people thought [Rubin] was nuts," but conceded that he knew what he was doing and what Android would become.

"Sundar Pichai will lead Android, in addition to his existing work with Chrome and Apps," wrote Page. "Sundar has a talent for creating products that are technically excellent yet easy to use - and he loves a big bet.

"Take Chrome, for example. In 2008, people asked whether the world really needed another browser. Today Chrome has hundreds of millions of happy users and is growing fast thanks to its speed, simplicity and security. So while Andy's a hard act to follow, I know Sundar will do a tremendous job doubling down on Android as we work to push the ecosystem forward."

By giving Pichai leadership of both Android and Chrome, Google could well be working to unify its two operating systems, as Apple has started to do with iOS and Mac OS X. This would tally with reports that Google Now is moving from Android to the Chrome desktop browser.

750 million Android activations

Page also revealed new milestones reached by the Android operating system: more than 750 million devices have been activated globally, Android has more than 60 manufacturer partnerships, and over 25 billion applications have been downloaded from the Play Store to date.

Horace Dediu of analytics company Asymco tweeted that the latest data his company has from Google "suggests an activation rate of about 1.4 million [Android devices] per day".

Dediu adds that the one billionth Android activation will be hit in mid-Angust, although the way in which Google counts new activations has been questioned, with some believing that a new activation is counted every time a phone is reset or sold on to a new user.